--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/http.py Sun Feb 08 03:17:07 2009 +0200
@@ -0,0 +1,227 @@
+"""
+ WSGI HTTP utility code
+"""
+
+# for utility functions
+import cgi
+
+# for header handling
+import wsgiref.headers
+
+# for path handling
+import os.path
+
+class Request (object) :
+ """
+ HTTP Request with associated metadata
+ """
+
+ def __init__ (self, env) :
+ """
+ Parse env data
+ """
+
+ # store env
+ self.env = env
+
+ # get the querystring
+ self.arg_str = env.get('QUERY_STRING', '')
+
+ # parse query args
+ self.arg_dict = cgi.parse_qs(self.arg_str, True)
+
+ @property
+ def site_host (self) :
+ """
+ Returns the site's hostname (DNS name)
+ """
+
+ return self.env['HTTP_HOST']
+
+ @property
+ def site_root (self) :
+ """
+ Returns the URL path to the requested script's directory with no trailing slash, i.e.
+
+ / ->
+ /foo.cgi ->
+ /foo/bar.cgi -> /foo
+ """
+
+ return os.path.dirname(self.env['SCRIPT_NAME']).rstrip('/')
+
+ @property
+ def page_prefix (self) :
+ """
+ Returns the URL path root for page URLs, based on REQUEST_URI with PATH_INFO removed
+
+ / ->
+ /foo.cgi -> /foo.cgi
+ /foo.cgi/index -> /foo.cgi
+ /foo.cgi/quux/bar -> /foo.cgi
+ /quux/foo.cgi/bar -> /quux/foo.cgi
+ /bar ->
+ """
+
+ # XXX: request uri path without the query string
+ request_path = self.env.get('REQUEST_URI', '').split('?', 1)[0].rstrip('/')
+
+ # path info
+ page_name = self.get_page_name()
+
+ # special-case for empty page_name
+ if not page_name :
+ return request_path
+
+ # sanity-check
+ assert request_path.endswith(page_name)
+
+ # trim
+ return request_path[:-len(page_name)].rstrip('/')
+
+ def get_page_name (self) :
+ """
+ Returns the requested page path with no leading slash, i.e.
+
+ /foo.cgi ->
+ /foo.cgi/ ->
+ /foo.cgi/bar -> bar
+ /foo.cgi/quux/ -> quux/
+ """
+
+ # the raw PATH_INFO
+ path_info = self.env.get('PATH_INFO')
+
+ # avoid nasty '.' paths
+ if path_info :
+ return os.path.normpath(path_info).lstrip('/')
+
+ else :
+ return ''
+
+ def get_args (self) :
+ """
+ Iterate over all available (key, value) pairs from the query string
+ """
+
+ return cgi.parse_qsl(self.arg_str)
+
+class Response (object) :
+ """
+ HTTP Response with headers and data
+ """
+
+ def __init__ (self, data, content_type='text/html', status='200 OK', charset='UTF-8') :
+ """
+ Create the response. The Content-type header is built from the given values. The given \a data must be
+ either a str (which is sent plain), an unicode object (which is encoded with the relevant charset), or
+ None, whereupon an empty response body is sent. The content_type argument can also be forced to None to
+ not send a Content-type header (e.g. for redirects)
+ """
+
+ # store info
+ self.status = status
+ self.data = data
+ self.charset = charset
+
+ # headers
+ self.headers = wsgiref.headers.Headers([])
+
+ # add Content-type header?
+ if content_type :
+ self.add_header('Content-type', content_type, charset=charset)
+
+ def add_header (self, name, value, **params) :
+ """
+ Add response header with the given name/value, plus option params
+
+ XXX: uses the wsgiref.headers code, not sure how that behaves re multiple headers with the same name, etc
+ """
+
+ self.headers.add_header(name, value, **params)
+
+ def get_status (self) :
+ """
+ Returns response status string (XXX Foo)
+ """
+
+ return self.status
+
+ def get_headers (self) :
+ """
+ Returns the list of header (name, value) pairs
+ """
+
+ return self.headers.items()
+
+ def get_data (self) :
+ """
+ Returns the response data - as an encoded string
+ """
+
+ if self.data :
+ return self.data.encode(self.charset)
+
+ else :
+ return ''
+
+class ErrorResponse (Response) :
+ """
+ A response with an error code / message
+ """
+
+ def __init__ (self, status, message, details=None) :
+ """
+ Build a plain error message response with the given status/message
+
+ @param status HTTP status code
+ @param message short message to describe errors
+ @param details optional details, plaintext
+ """
+
+ data = """\
+<html><head><title>%(title)s</title></head><body>
+<h1>%(title)s</h1>
+<p>%(message)s</p>
+%(details)s
+</body></html>
+""" % dict(
+ title = status,
+ message = message,
+ details = '<pre>%s</pre>' % details if details else ''
+ )
+
+ super(ErrorResponse, self).__init__(data, status=status)
+
+class ResponseError (Exception) :
+ """
+ An exception that results in a specfic 4xx ErrorResponse message to the client
+ """
+
+ def __init__ (self, message, status='400 Bad Request', details=None) :
+ self.status = status
+ self.message = message
+ self.details = details
+
+ super(ResponseError, self).__init__(message)
+
+ def get_response (self) :
+ return ErrorResponse(self.status, self.message, self.details)
+
+class Redirect (Response) :
+ """
+ Redirect response
+ """
+
+ def __init__ (self, url) :
+ """
+ Redirect to given *absolute* URL
+ """
+
+ # no content-type or data
+ super(Redirect, self).__init__(None, content_type=None, status='302 Found')
+
+ # add Location: header
+ self.add_header("Location", url)
+
+